Efficiency evaluation of Zinc and Nickel removal through coagulation and flocculation process using chitosan

Background: the release of large quantities of zinc(zn) andnickel(ni) into the natural environment cause someenvironmental problems. the aim of this research wasinvestigation the effect of chitosan biopolymer as a naturalfluctuant in order to remove zn2+ and ni2+ from aqueoussolutions.material and methods: experiment in batch system as the halfexperiment study with change in effective parameters such asph (6-9), dose of coagulant (10-100 mg/l), settling time andinitial amount of metal was investigated.results: results of this study showed that zn2+ and ni2+removal increases with ph increases. the optimal amount ofcoagulant used for this study was defined between 60 - 100 mg /l respectively. so the results of this study also showed thatinitial concentration of metal had inverse relation with zn andni removal efficiencies in coagulation and flocculationprocesses.conclusion: due to chitosan properties such asbiocompatibility, biodegradability, ability to remove heavymetals and also having amine, hydroxyl and carboxylic functiongroups it can be use as a coagulant and/or flocculant to removeheavy metals from aqueous solutions.